DESCRIPTION: The goal of this research is to test the hypothesis that sodium channel beta subunits interact with extracellular matrix molecules, membrane receptors, and intracellular signaling proteins to modulate cell adhesion. Specifically, the first aim will identify the domains of tenascin-R responsible for binding to the Nay 1.2 and the beta-1 subunit of the sodium channel using gel overlay and coimmunoprecipitation assays. The second aim examines the ability of beta-1 to interact with the FGF receptor during ligand binding and homophillic events to cause downstream signaling. The final aim examines whether potential SH2 and SHPTP-2 binding motifs within the intracellular domain of beta-1 are able to recruit non-receptor tyrosine kinases such as lck, fyn or crk. Since mutations in cell adhesion molecules, including sodium channel beta-1 subunits, are linked to several inherited diseases; a basic understanding of the biology of cell adhesion associated with sodium channel beta-1 subunits and like molecules may lead to therapeutic advances for these debilitating diseases.